learned more this past week about one type of weapon in the u.s. arsenal. we've learned that more than 11 years of american combat overseas. we found out about the administration's legal justifications for the use of drones, that catch-all term for an expanding family of unmanned flying military hardware. the week's revelations further fueled the public debate about the propriety of drone strikes against human targets as we'll hear this morning beginning with martha teichner's report on our sunday morning cover story. >> reporter: so you think you know what a drone is? one of those unmanned aircraft that takes out terrorists. well, think again. this is a drone too. tell me what that is. so is this. and would you believe a humming bird drone? ahead this sunday morning, technology both tantalizing and troubling. >> osgood: the grammy awards are tonight here on cbs. among the nominees you can find the name john mayer. after a period on the performance side lines mayer' is preparing to move back into the spotlight as we'll be hearing from anthony mason. >> reporter: why did you come out here?